Furniture stabilizing device



Jan l 1957 F. w. INGRAM 2775849 FURNITURE STABILIZING DEVICE Filed July 7, 1954 United States Patent O ce FURNITURE STABILIZING DEVICE K Frank W. Ingram, Erdington, Birmingham, England Application July 7, 1954, Serial No. 441,879

Claims priority, application Great Britain July 16, 1953 3 Claims. (Cl. 45-139) My invention relates to stabilizing devices lwith particular reference to items of furniture which are unstable due to irregularities in the length of the legs or feet of such furniture or to standing upon an uneven surface.

The increasing use of light tubular steel and wooden furniture, particularly in licensed premises and restaurants, emphasizes the advantage of such furniture that it may be slid away to permit cleaning of the floor upon which it normally stands or that it may be removed to allow the floor space to be used for some other purpose, e. g. dancing or cabaret.

Unfortunately, however, due to constantly changing the position of such furniture, irregularities in the level of the lloor and the length of the legs of the furniture, it is often the cas-e when such furniture is returned to a position on the floor it is -found to be standing on three legs only and as a result is unstable.

The instability can be the cause of intense irritation to customers and patrons, 4and is frequently the cause of considerable damage to clothing by virtue of the upsetting of liquid containers standing upon the furniture, by waiters, persons or animals brushing against the items of furniture.

yIn order to eliminate the instabili-ty, it is necessary to supply means to close the gap between the offending leg or foot and the surface upon which it stands.

It is also necessary that such means shall automatically adjust themselves to differences in the size of the gap corresponding to different positions of the furniture rela- .tive to the surface upon which it stands, 'and also to offer a substantially solid resista-nce to such movement of4 the furniture as is likely to cause the accidental upsetting of containers previously referred to.

llt is an object of the present inventionV t-o supply such means and i-t is a further object of the invention to supply an article of furniture having a leg or legs which incorporate distensible means for `automatically tilling lany gap which may exist between one of such legs when the furniture is stood upon a -oor or like base upon the other legs of the furniture.

According to the present invention, a dev-ice for stabilizing an article of furniture comprises a plug or the like secured to and movable relative toa member and resilient means urging said plug away from said member wherein said plug is moved toward said member at a controlled speed and said resilient means are collapsed when a minor proportion of ,the weigh-t of said article of furniture is borne by the device.

The member may be the item of furniture but preferably the plug is slidable in a housing which is adapted to be secured within Ea recess formed in .a 4leg or like support of the article of furniture so that it is immovable relative thereto.

Preferably also the resilient means is a spring but a resilient metallic bellows member, being in itself a spring, may also be used.

The function of the resilient means, however, is limited to that of extending the device when a condition of No- Patented Jan. 1, 1957 2 Load is applied. It is not -a function of the resilient means to support the table in any way and these means should be sufficiently light to collapse under a load of e. g. 12 ounces.

The means for controlling the speed of movement of the plug may -comprise `a piston and cylinder mechanism whereby hydraulic iluid in the cylinder is permitted to leak slowly past the piston or, alternatively, it may comprise a friction member engaging a rod with a predetermined degree of frictional resistance.

It is preferable also that control of the speed of movement of the plug relative to the member be exercised mainly when the plug is moving toward the member in order that the resilient means may be free to extend the plug from the member in the shortest possible time.

In a preferred embodiment a tubular housing is closed at one end and a hollow plug also closed at one end is slidable within the open end of said housing. A helical spring is enclosed within the housing having one end abutting the closed end thereof, and the other end abutting the adjacent end of the plug. The means for controlling the speed of movement of the plug comprises a piston slidable within the plug which projects from the housing and which is partially filled with hydraulic fluid. The piston is connected by means of a rod to the closed end of the housing and is adapted for limited movement relative to said rod between two axially spaced locating washers. A bush is secured to the open end of the plug having a concentric bore in which the piston rod is slida-bly supported, and a plurality of grooves is formed on that face of the piston remote from said housing In a further embodiment of the inven-tion, the plug is solid, andthe housing is tubular and divided into an upper and a lower chamber by a partition fluid tightly secured within the bore thereof. A distensible bellows member h-aving a helical spring lassociated therewith, or being in itself resilient, is enclosed within the lower chamber, one end thereof being fluid tightly secured to the said partition and the other end abutting that end of the plug permanently enclosed within the housing. A metering hole formed in said .partition and in that end of the distensible member lluid tightly secured thereto connects the interior of said distensible member lwith the upper chamber formed by the partition within the housing whereby iluid may pass from said dis-tensible member to the upper chamber when the distensible member is longitudinally contracted. A rod secured to the partition and extending into the interior of the distensible member limits the movement of Said distensible member upon contraction, and a ball valve within the metering hole permits -a more rapid llow of fluid for one direction of movement of the plug than for the other.

In yet a further embodiment of the invention, the plug is hollow but closed at one end and has a bush secured within the open end thereof, said bush having a co-axially aligned taper bore, the larger diameter end of which lies remote from the closed end of the plug. A rod extending from the closed end of the housing is adapted to pass coaxially through said taper bore, and a flange formed on that end of the rod remote from the closed end of the housing .is adapted to engage one end of said bush to prevent the rod from leaving the bush. A plurality of segmental shaped wedges of friction material are located round the rod within the taper bore, whereby the rod is gripped by the wedge action of the said wedges when moved in one direction, but extracts the wedges from the taper bore when moved in the other direction. A light helical spring having one end abutting the closed end of the housing retains the wedges within the taper bore and a further helical spring of larger diameter, abuts the closed end of the housing at one end and the plug at the other end. s

In order that the invention may be more fully described, reference is made to the accompanying drawings of which:

Figure 1 iis 'a section of a stabilizing device constructed according to the invention.

Figure v2 is an end view of a piston to be incorporated in the embodiment shown in Fig. 1.

Figure 3 is a sectional view 'of an alternative embodiment of the invention.

Figure '4 is a sectional view of -a further embodiment of the invention.

Figure 5 is a part sectional view of a table leg having a stabilizing device constructed according to the invention, vsecured thereto.

Figure 6 is a 'sectional view of alternate means of securing a stabilizing 'device of the present invention to a leg 'or support 'of a tubular lsteel item of `furniture.

In one embodiment of the invention (Figs. 1 and 2) a cylindrical plug y1l, closed at one end is slidable within a cylindrical housing 2, which is also closed at one end. A `cylindrical bush 3 is secured within the lopen yend of the plug 1, the bore 'of which is coaxially valigned with the bore of the cylindrical plug 1. A piston-rod 4extends through said bush 3 and is secured to the end wall of the housing 2 by means of a nut 6 which 'engages with a threaded portion of the piston rod 4, :and an annular piston "5 (Fig. 2) having an internal diameter larger than vthe diameter of said piston rod 4 .is located thereon between locating washers 7 and 8. lA plurality of grooves 9 'are formed .in `that face of the Apiston adjacent the closed end of the plug 1 and sufiicient hydraulic fluid is contained in the plug to fill it completely when the locating washer 7 abuts the vclosed Vend thereof. A helical spring 10 is enclosed within the vhousing A2, yone end fof which abuts 'the end wall of said housing 2 and fthe Iother end abuts the adjacent vend of the 'plug 1. A sealing ring 11 is ilocated 5in a groove 11a formed inthe bush 3 to prevent the -escapeof hyd raulic'fiuid from the plug.

The `device operates as follows. When 'the plug 1 is moved inwardly of the housing `2 yagainst the action 'of the 'helical spring 1), the force moving the plug 1, hereafter described as the compressing force, lis resisted by the reaction of the piston 5 against 'the hydraulic fluid, the l.piston 5 being forced against the washer `8 to prevent the flow of hydraulic 'fluid past the inner periphery `of lthe piston, but if 'the compressing force is maintained, hydraulic fiuid ows past the piston -5, between the outer periphery thereof and the walls of the plug 1 at a 'rate dependent upon the clearance between said outer yperiphery Sand said walls for a given compressing force, whereby the Jd'evice iseventually contracted to the point where vthe locating washer 7 abuts the closed end of the plug 1. I'When'-thecompressing force is removed, theihelical spring '10 moves -the plug 1 outwardly ofthe housing 2 and the washer 7 thus moves to abut the piston 5. This movement provides -a ffree passage for the hydraulic fluid, past 'the inner periphery of the piston 5 and along the `grooves`9 formed in the face thereof thus permitting rapid expansion of the device to the point wherein the locating washer 8 'abuts the bush 3 to prevent further-expansion.

:One Such device is fitted into the end of each Vleg 32 El(1F-ig. v5) for support of an item 'of furniture e. g. a table fh'avi'n'g four legs, so that when the table stands upon Iits *legs J'on an irregular oor or like surface the closed end of the '-plug 1 abuts the floor and the deviceis at substanh tiallylright angles to the said floor. At least three of the legs thereof will be in contact with the floor and the device of 'the fourth leg will vbe suspended some distance La'bove the fioor, and fully extended by the action of the helicalspring 10. Due tothe weight of the'table, pressure -willbearon'those three devices contacting 'the fioor'which twill 'causeithem to becontracted inthe manner previously idescri'b'ed. The contraction 'will continue until the gap fbetween ltheldevice of -the `fourth -leg is taken up and this device will then contract with the other three until these "chamber v18. however, `lfluid continues to ow Fslowly past the quick three are fully contracted and wholly contained within the leg or support of the item of furniture.

With the table in this position, any sudden pressure brought to bear on any of the legs of the table will be thus solidly resisted, either by the reaction of the piston of the device on the hydraulic fluid or by the end of the leg on the floor if the particular device secured to that leg is fully contracted.

Sustained pressure, however, if directed to a device which is 4notzfffully contracted, hereinafter described as Vthe device under consideration, w-ill cause it to be further contracted in the manner previously described, the speed of 1such contraction Ybeing controlled by the clearance between the outer periphery of the piston of the device and the walls of the plug, the table meanwhile pivoting upon those two legs adjacent to and at substantially right angles to the leg holding the device under consideration. The device :of theremaining leg :i. e. Vthe leg diametrically opposite, will, however, extend under the action of its helical spring in .direct proportion to the 'amount of contraction of said device under consideration7 so that at all times 'a'll four devices are in contact with theiioor or like surfaceupon which the table stands.

While the .foregoing embodiment has described a plug slidabl'e in a Ahousing it .should be understood that the housing `is not essential and in the case e. g. of tubular furniture, `the plug may Aslide in .a tube 33 (Fig. 6) forming a leg or support, having an abutment 34formed within the Ainner periphery thereof, to which that end of 4the piston rod 4 'remote from the .plug 1, may be secured. In such a fcase, Athe hollow plug .1 .may vbe sealed with a 'closure member .35 :to facilitate ease of assembly.

In ea Lfurther fembodiment yof the invention, Fig. 3, a solid plug 12 having a radially outwardly extending taper portion 13 artf'on'e end thereof is slidably located in a tubular housin'g 14. The housing 14 is formed having one portionth'ereof of smaller cross sectional Varea than the remaining portion, kthe portions being connected by a :tapering portion 41S, 'the inner periphery of which provides an abutment, against which the taper portion 13 of the plug =12Ymaybe located.

'Ehe 1plug 12 is slidably supported -by the inner periphery of that portion lof -the housing of 4smaller `cross sectional area land when the 'taper portions 15' and 13 are abutting the lend of the plug 12 remote 4from the taper port-ion 13 projects beyond the end -of the said portion of smallericross sectional area.

A -partition 156 is fluid tightly secured -to the inner periphery iof the vlarger -portion of the housing 14 4intermediate, the ends thereof whereby Atwo chambers 17 and 18 are formed. A resilient bellows member 19 having onesea'led en'd is located in chamber 17, the open end thereofbeing fluid tightly secured yto said 'partition 16, 'and thesealed-endabutting-theladjacent'end'of theplug'12. -A stem l20 securedfto-the partition 16 extends into the bel- :lowsmember infaxial Valignment therewith and a metering hole 21 is formed in the partition A16. A quick 'return valve of known -type vcomprising a -ball movable by lfiuid Apres- -sure to'seal the major portion of an orifice and not claimed asl part of -the'present invention is inserted in said metering hole lfor a-purpose to be later described,and a closure member 22 -is secured in that endfof the Ahousing 1'4 remote 'from the plug i2. The distensible Vbellows -member is filled with hydraulic fluid anda-helical spring 23 enclosed in chamber 17 has one end abutting the partition 'and ythe other -en'd 'abutting the adjacent end of -the plug 12.

The :device'operates as follows. When the plug 12 is Amoved inwardly of the housing 14 against lthe action of the helical spring 23, the compressingforce is resisted by the hydraulic fluid in the bellows member, which in turn .is ibein'g compressed 'between the plug -12 and the partition 16, andthe reactionfof the quick'return valvewhich allows only a small quantity of fluid lto fiow into the "lf the compressing force vis maintained,

5 return valve into the chamber 18 and the bellows member contracts longitudinally until the end which lies adjacent the plug 12 abuts the end of the stem 20 and restricts further movement of the plug in this direction.

When the compressing force is removed, the helical spring 23 moves the plug outwardly of the housing, the quick return valve permitting a rapid iiow of fluid in this direction from chamber 18 to chamber 17 whereby the device extends rapidly to the point where the taper portion 13 of the plug 12 `abuts the taper portion 15 of the housing to restrict further movement of the plug in this direction.

While this embodiment has described a distensible bellows member co-operating with a helical spring 23, it should be understood that the bellows member may be metallic, and in itself su'iciently resilient to eliminate the necessity for such a spring.

One such device is fitted into the end of each leg or support of an item of furniture in the manner described in the previous embodiment and functions in a similar manner to stabilize the item of furniture.

In yet a further embodiment of the invention (Fig. 4) a cylindrical plug 24 closed at one end is slidable within a cylindrical housing 25 which is also closed at one end. A cylindrical bush 26 is secured within the open end of the plug 24, the bore of said bush being tapered and coaxially aligned with the bore of the cylindrical plug 24 and has the larger diameter thereof at that end of the bush 26 remote from the plug 24. A rod 27 extends coaxially through the taper bore of the bush 26 having one end secured to the end wall of the housing 25 and the other terminating in a radially extending iiange 2S of larger diameter than the smaller diameter of the taper bore of the bush 26.

A plurality of substantially wedge shaped members 29 of segmental cross section and being formed of friction material are enclosed within the space between the taper bore of the bush 26 and the adjacent periphery of the rod, being retained therein by a helical spring 30 one end of which abuts the end wall of the housing 25 and the other end of which abuts the adjacent ends of the wedge shaped members 29. A further helical spring 31 is located within the housing 25, one end abutting the end wall thereof and the other end abutting the adjacent end of the plug 24.

The device operates as follows. When the plug 24 is moved inwardly of the housing 25 against the action of the helical springs 30 and 31, the compressing force is resisted by the frictional resistance between the wedge shaped members 29 and the rod 27, such force being increased by the tendency of the rod 27 to force the f wedge shaped members 29 further into the taper bore of the bush 26. When a predetermined compressing force is exceeded, however, the wedge shaped members 29 slide along the rod 27 and permit the plug 24 to move inwardly of the housing 25, such movement being restrained by the frictional resistance. This movement may continue until the helical spring 31 is fully compressed and forms a solid tube between the end wall and the housing 25 and the end of the plug 24.

When the compressing force is removed the helical spring 31 moves the plug 24 outwardly of the housing 25 whereby the wedge shaped members are drawn outwardly of the taper bore of the bush 26 thereby reducing the value of the frictional resistance between said members 29 and the rod 27, thus permitting rapid expansion of the device to a point whereby the flange 28 abuts the adjacent end of the bush 26, to prevent further movement of the plug 24 relative to the housing 25.

The device is tted to an item of furniture and functions to produce the stabilizing effect as described in the previous embodiments.

While the invention has been described showing one device secured to each leg or support of an item of furniture, it should be understood that this is not essential. in the case of e. g. a wardrobe which is not likely to be moved from one position upon a door, the use of a single device secured to a single leg or like support could adequately deal with an irregularity in the floor level at that particular position.

Furthermore, casters or other known devices to per mit ease of movement of such items of furniture may be secured to the movable plug portion of my stabilizing device, or be formed as an integral part thereof, and Similar stabilizing devices having means to increase the area of contact between an item of furniture and the floor or support on which it stands are considered to be within the scope of my invention.

Having now described my invention, what I claim is:

1. A furniture stabilizing device which comprises a housing open at its lower end, a hollow plug slidable vertically in said housing and closed at its upper end, a rod secured to the upper part of said housing and extending co-axially substantially uid tightly and slidably through the closed upper end of said plug into said plug, said rod having a pair of spaced surfaces within said plug to form an annular recess, a spring pressing said plug downwardly to project from the lower end of the housing and a floating annular disc in said recess and having a slight clearance with the inner peripheral surface of said plug to form a restricted passage therewith, said disc being movable to a fluid-tight contact with the upper surface of said recess and movable to a fluid-free contact with the lower surface of said recess, said recess and disc providing passages for the fluid when in contact.

2. The furniture stabilizing device of claim l in which the lower surface of said floating annular disc is grooved to provide fluid passages when said disc is in contact with the lower surface of said recess.

3. The furniture stabilizing device of claim 1 in which said hollow plug contains a liquid.

References Cited in the tile of this patent FOREIGN PATENTS 325,656 Great Britain Feb. 27, 1930 485,362 Canada Aug. 5, 1952 640,708 Germany Ian. 11, 1937 

